Testicle
The male gonad; produces sperm and male sex hormones.

Testicular biopsy
The removal of a fragment of a testicle for examination under the microscope.

Testicular Sperm Extraction (TESE)
A procedure for extracting sperm by removing a small piece of testicular tissue through an incision in the testes. In the laboratory, the tissue is processed to extract sperm for use with ICSI.

Testosterone
The primary male sex hormone.

Therapeutic abortion
A pregnancy ending in an induced abortion using an operative procedure to electively terminate the pregnancy.

Thyroid gland
The endocrine gland in the front of the neck that produces thyroid hormones, which regulate the body’s metabolism.

Tocolytic
A drug that relaxes smooth muscles and therefore interferes with uterine contractions; frequently used to stop premature labor.

Total effective sperm count
An estimate of the number of sperm in an ejaculate capable of fertilization; total sperm count X percent motility X percent forward progressive motility X percent normal morphology.

Toxin
A poison produced by a living organism, such as by some bacteria.

Transabdominal transfer
The transfer of embryos or oocytes by placement of a catheter via laparoscopy through the fimbria.

Transcervical transfer
The transfer of embryos or oocytes by placement of the catheter through the cervix.

Transuterine falloposcopy
Visual inspection of the fallopian tube through a flexible endoscopic device (falloposcope).

Tubal embryo transfer
The ZIFT-like technique using an embryo in its early stages of development (see zygote intrafallopian transfer). 

Tubal Factor
A cause of infertility related to structural or functional damage to one or both fallopian tubes.

Tubal ligation
Surgical sterilization of a woman by obstructing or “tying” the fallopian tubes.

Tubal patency
Unobstructed Fallopian tubes.

Tuboplasty
Plastic or reconstructive surgery on the fallopian tubes to correct abnormalities that cause infertility.

Tumor
An abnormal growth of tissue that can be benign or malignant (cancerous).

Two-way split ovum donation cycle
A Donor/Recipient IVF cycle in which the eggs retrieved from te donor are shared by two recipients after fertilization.